Targeting cellular batteries for the therapy of neurological diseases

Environmental Science and Pollution Research - The mitochondria, apart from being known as the cell’s “powerhouse,” are crucial in the viability of nerve cells. Any damage to...     

Degradation activity of Clostridium species DC-1 in the cis-1,2-dichloroethylene contaminated site in the presence of indigenous microorganisms and Escherichia coli

We showed the cis-1,2-dichloroethylene (cis-1,2-DCE) dechlorination ability of Clostridium species DC-1 in association with other bacteria. Result of denaturing gradient gel electrophoresis showed the dominant band pattern of DC-1 during the degradation time of cis-1,2-DCE and dominance of some other Clostridium species. Experiment with addition of Escherichia coli (E. coli) showed that dechlorinating activity of DC-1 was not inhibited by the presence of E. coli. Pour plate experiment with DC-1 and E. coli revealed that the dominance of Clostridium species caused the decrease of E. coli growth in a bioremediation state. This result suggested the possibility of Clostridium species DC-1 as a degrader of cis-1,2-DCE, in a cis-1,2-DCE contaminated site where an indigenous microbial community is present. Experiment conducting with E. coli suggested that the strain in the contaminated site did not inhibit the degradation of cis-1,2-DCE and during the degradation period, rather some other Clostridium species became dominant and the growth of E. coli would be decreased. This finding could be a very positive approach for implementing the dechlorinating bacteria at aliphatic chlorinated component contaminated sites.     

Amelioration of arsenic toxicity by phosphate salts in mungbean seedlings

Sodium arsenate (Na2HAsO4.7H2O) is a potent inhibitor of mungbean seed germination and seedling growth. Germination is totally stopped at or above 50 microM Na2HAsO4.7H2O. Inhibition of seedling elongation started at a lower concentration of 5 microM As(V) and was drastically reduced at 20 microM As(V). Nutrients like salts of macroelements viz., NaH2PO4.2H2O, KH2PO4, K2SO4, MgSO4.7H2O, CaCl2.2H2O, (NH4)2SO4 NH4NO3 solutions at a concentration of 10mM and microelements viz., ZnSO4, CuSO4.5H2O, Na2MoO4.2H2O, MnCl2.4H2O, CoCl2.6H2O, FeSO4.7H2O solutions at a concentration of 1mM could help to ameliorate the toxic effects of As(V) to different degrees. Amelioration of As(V) toxicity was possible only when the mungbean seeds were pretreated with the above mentioned nutrients for 24 hr and then transferred to sodium arsenate. Simultaneous treatment of nutrients with As(V) or using nutrient solutions following As(V) treatment were of no help to reverse the toxic effects of sodium arsenate.     

Cloning and expression of α-amylase in E. coli: genesis of a superior biocatalyst for substrate-specific MFC

One of the most practical approaches for establishing a successful microbial fuel cell (MFC) is to fasten the oxidation rate of the substrate by the microorganisms to get quick paced electron transfer between microbes and electrode. A genetically modified Escherichiacoli, overexpressing α-amylase, is constructed and applied as biocatalyst in MFC using starch as substrate. The results are compared with nonrecombinant, native E.coli. The results show better performance for the MFC containing the recombinant strain demonstrated by higher power density (PD), lower resistance, and significant electrochemical activity. Maximum PD has been recorded as 279.04 mW m^?2 compared to 120.33 Mw m^?2 for the MFC operated with nonrecombinant E.coli. The impedance results also suggest the effectiveness of the recombinant strain by lowering the internal resistance by more than half order as compared to the nonrecombinant one. These results affirm that the engineered strain can be used as a superior biocatalyst in contrast to the native strain and by using the technique of genetic alteration; gene of interest can be inserted based on the substrate to be treated. So, this work gives a useful insight for accomplishing successful MFC operation with the use of bacterial stains engineered at the molecular level.     

Indifference curves as a tool for environment impact assessment

Use of indifference curves, defined as functionality between development index and pollution load to evaluate environmental impact, is proposed. Existing Battelle environmental evaluation methodology is subjective in its approach. The use of indifference curves lends a more objective approach to environment assessment methodology. The extent of environmental damage we are prepared to accept, for a development, can be explained by Willingness to Pay and Willingness to Accept approach. The application of proposed approach has been demonstrated taking an example of Power plant set up in forest area. The curves clearly show that cost of EMP considering mitigation of ecological damage is higher than the EMP mitigating impacts of air and water pollution only. The example stresses the need for willingness to accept along with willingness to pay.     

Microbial dynamics in the process of restoration of groundwater contaminated by chlorinated ethene in the presence of Escherichia coli

This study investigated the effects of hygiene indicator bacteria during the biostimulation of groundwater contaminated with chlorinated ethene. We showed the state of dechlorination activity and behavior of microbial structure by the addition of Escherichia coli (E. coli) as hygiene indicator bacteria in a contaminated groundwater sample. Dechlorination of tetrachloroethene and trichloroethene to cis-1,2-dichloroethene (cis-DCE) within 14 days took place similarly both with and without the addition of E. coli. This indicated that inhibition of against dechlorinating activity of corresponding dechlorinating bacteria was not caused by E. coli. Structural change of the bacterial community was analyzed both before and after dechlorination using a denaturing gradient gel electrophoresis (DGGE) and clone library. The result of DGGE detected E. coli only at day 0. A sample at day 14 after dechlorination detected Pseudomonas putida, Anaerosinus glycerini, and Clostridium genus but not E. coli. The result of the clone library also showed an identical profile. Detection of E. coli using desoxycholate media was decreased from 2.3 × 10⁶ cells/ml to 6.0 × 10³ cells/ml during day 14. These results suggest that biostimulation of groundwater contaminated by chlorinated ethene in the presence of hygiene bacteria caused the dechlorination without activity inhibition and decrease of dechlorinating bacteria.     

Comparison of carbon footprints of steel versus concrete pipelines for water transmission

The global demand for water transmission and service pipelines is expected to more than double between 2012 and 2022. This study compared the carbon footprint of the two most common materials used for large-diameter water transmission pipelines, steel pipe (SP) and prestressed concrete cylinder pipe (PCCP). A planned water transmission pipeline in Texas was used as a case study. Four life-cycle phases for each material were considered: material production and pipeline fabrication, pipe transportation to the job site, pipe installation in the trench, and operation of the pipeline. In each phase, the energy consumed and the CO₂-equivalent emissions were quantified. It was found that pipe manufacturing consumed a large amount of energy, and thus contributed more than 90% of life cycle carbon emissions for both kinds of pipe. Steel pipe had 64% larger CO₂-eq emissions from manufacturing compared to PCCP. For the transportation phase, PCCP consumed more fuel due to its heavy weight, and therefore had larger CO₂-eq emissions. Fuel consumption by construction equipment for installation of pipe was found to be similar for steel pipe and PCCP. Overall, steel had a 32% larger footprint due to greater energy used during manufacturing.

Implications: This study compared the carbon footprint of two large-diameter water transmission pipeline materials, steel and prestressed concrete cylinder, considering four life-cycle phases for each. The study provides information that project managers can incorporate into their decision-making process concerning pipeline materials. It also provides information concerning the most important phases of the pipeline life cycle to target for emission reductions.